W Seal

Background
Compression seal has been used to seal movements of less than 75 mm for nearly 40 years. The compression seal relies on the force created by the internal web configuration to apply enough pressure against the sidewall of the expansion joint to remain watertight. In many cases, after a few years, the seal hardens and the “compression set” of the polymer reduces the force being applied against the sidewall and, therefore, does not permit the seal to remain watertight. The hardening of the seal also prohibits the adhesive from being able to pull the seal open when the expansion joint contracts.